Fragility and thermal expansion control crystal melting and the glass transition

Alessio Zaccone; Konrad Samwer

doi:10.1063/5.0253991

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arXiv · 2503.13270

Fragility and thermal expansion control crystal melting and the glass transition

Alessio Zaccone·Konrad Samwer

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Abstract

Analytical relations for the glass transition temperature, $T_g$, and the crystal melting temperature, $T_m$, are developed on the basis of nonaffine lattice dynamics. The proposed relations explain: (i) the seemingly universal factor of $\approx 2/3$ difference between glass transition temperature and melting temperature of the corresponding crystal, and (ii) the recent empirical discovery that both $T_g$ and $T_m$ are proportional to the liquid fragility $m$ divided by the thermal expansion coefficient $\alpha$ of the solid.

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cond-mat.soft cond-mat.dis-nn cond-mat.mtrl-sci cond-mat.stat-mech physics.chem-ph

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Alessio Zaccone, Konrad Samwer. 2025-03-17. Fragility and thermal expansion control crystal melting and the glass transition. https://doi.org/10.1063/5.0253991

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